This invention concerns a polyether end-blocked with hydrolyzable silyl groups that can be cured at room temperature into a rubber-like elastomer upon contact with moisture, and a method of manufacturing the same. This invention also relates to a room temperature curing composition comprising such a polyether as an ingredient. The room temperature curing composition cures to a rubbery elastomer having particularly good heat and weather resistance, and having good adhesion before cure with no residual tackiness on the surface after cure.
The room temperature curing composition of this invention, comprising the above polyether, is suitable for use as a sealant. Similar prior art polyethers as well as their use in sealants are well known as disclosed in Japanese patent publication Kokai No. 50-156599, etc. Sealants based on such polyethers have been employed for the joints of buildings or joining portions in transportation machines (Japanese patent publication Kokai No. 52-73998, etc.) However, since the prior art sealants of this type are poor in heat resistance and weather resistance, they are undesirable for use in the joints of building outer walls requiring weather resistance, or in joints exposed to a relatively high temperature, for example, certain joining portions in transportation machines. Further, since the sealants of this type have no adhesive property, it is necessary to give adhesiveness to the sealants either by treating substrates with primers or by incorporating silane coupling agents in the sealant compositions. However, primer treatment is disadvantageous in terms of processability, whereas incorporation of silane coupling agents lowers the elongation of cured sealants and makes them brittle, even if adhesive property is given. Additionally, since the surface of cured sealant remains tacky, there is a problem that dust or the like may be stuck to the sealant.
The object of this invention is to overcome these problems and a further object thereof is to provide a room temperature curing composition capable of curing to a rubbery elastomer having good heat and weather resistance, and having good adhesion before cure with no residual tackiness on the surface after cure. This invention further provides a polyether end-blocked with hydrolyzable silyl groups which is useful as a base polymer in sealants, as well as a process for producing such a polyether.